Fair Value Of Financial Instruments (Schedule Of Changes In Fair Value Associated With Level 3 Financial Instruments) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2025 USD ($)
Asset-Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	$ 1,034
Purchases	9,131
Net change	9,131
Ending Balance	10,165
Syndicated Loans [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	58,467
Unrealized gains/(losses)	52
Purchases	8,900
Redemptions	(24,060)
Net change	(15,108)
Ending Balance	43,359
Corporate Equity Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	15,565
Realized losses	(404)
Purchases	336
Net change	(68)
Ending Balance	15,497
Auction Rate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	558
Unrealized gains/(losses)	(6)
Net change	(6)
Ending Balance	552
Other Investment [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	14,348
Unrealized gains/(losses)	47
Realized losses	(755)
Net change	(708)
Ending Balance	$ 13,640